(1) Field of the Invention
The present invention relates to aluminum nitride-based sintered bodies, corrosion-resistant members, metal-buried articles and semiconductor-holding apparatuses.
(2) Related Art Statement
With the increase in the memory capacity of the super LSIs, finer processing has come to be necessary, which makes chemical reaction-requiring processes to be more extensively used. Particularly in the semiconductor-producing apparatuses that require a super clean state, halogen-based corrosive gases such as chlorine-based gases or fluorine-based gases are used as deposition gases, etching gases or cleaning gases.
After the deposition, a semiconductor-cleaning gas composed of a halogen-based corrosive gas such as ClF.sub.3, NF.sub.3, CF.sub.4,HF or HCl is used in a heating apparatus in which an objected is to be heated while being contacted with the corrosive gas, for example, in the semiconductor-producing apparatus such as a hot CVD apparatus. Further, a halogen-based corrosive gas such as WF.sub.6 or SiH.sub.2 Cl.sub.2 is used as a film-forming gas in the deposition state.
NGK Insulators, Ltd. disclosed in JP-A-5-251,365 that aluminum nitride sintered bodies each having a layer of aluminum fluoride on the surface exhibit high corrosion resistance against a plasma of the above halogen-based corrosive gas. That is, even when the aluminum nitride sintered body was exposed to, for example, ClF3 gas for one hour, its surface state did not change.
Further, NGK Insulators, Ltd. disclosed in JP-A 5-251,365 that a film of aluminum fluoride is formed on a surface of an aluminum nitride sintered body by a gas phase method such as CVD. JP-A 7-273,053 discloses that in order to prevent the corrosion of the surface of an electrostatic chuck for semiconductor wafers, the surface of the electrostatic chuck is preliminarily replaced by fluorine to produce AlF.sub.3 at the surface of the chuck.
However, the above techniques regarding the aluminum nitride-based sintered bodies are all aimed at the formation of the corrosion-resistant surface layers, and their producing processes are complicated.